/**
 * Created with IntelliJ IDEA.
 * Description:
 * user:likai
 * Date:2022-09-28
 * Time:8:01
 */

//class B extends A{
//
//}
//abstract class D extends A{
//
//}
abstract class A{
    int a;
    abstract void f();
    public A(int a){
        this.a=a;
    }
}
class C extends A{

    public C(){
        super(2);
    }
    @Override
    public void f() {
        System.out.println("可以运行");
    }
}

public class Test {
    public static void main(String[] args) {
        C c=new C();
        c.a=1;
    }
}
